Sure, if transhuman predictions come to pass, we'll be cosmically important. On the Kardashev scale, for example, we might become a Type III species, able to harness the galaxy and affect not just the course of our planet, but that of much of the universe.
Possibly, though, those predictions are grandiose dreams akin to theistic myths. I talk about transhumanism, but I doubt we can show that the technological predictions are likely to come true. The greater our technological power, the more damage we do to nature, and the more we sabotage our position in the biosphere. To live as a god means living apart from nature, and I doubt we have the stomach for that, to be a spacefaring species.